For years, fittings and connections to copper orsteel tubing have included connections commonly known as "flared" wherein the end of the tube is outwardly flared to define a conical female surface for seating against a conical male surface. A nut mounted upon the tube forces the flared portion into engagement with the associated fitting. In the past, the flaring of tubes has been accomplished by a variety of tools, both of the manual and power type.
Conventional flaring tools may take the form shown in U.S. Pat. Nos. 1,795,358; 2,117,543 and 2,430,168. Also, it has been common to utilize a split bar arrangement for holding the tube during flaring, and such bars usually include a plurality of different size holes to accommodate standard tube sizes, such as shown in U.S. Pat. Nos, 2,242,831 and 3,575,033.
The particular form and configuration of the flare formed in the tube may vary, but in most tools the flaring is accomplished by a conical tool surface being axially forced into the tube end which flares the tube end in accordance with the configuration of the die recess formed in the holder. Thus, a single size and shape of conical tool surface can be used to flare various sizes of tubes.
However, some types of tube flaring requires a special size tool for each size of tube, and an example of such a tube flare configuration is shown in U.S. Pat. No. 4,047,415. In such instance wherein the flaring tool must be specially sized for each tube it is necessary to provide a complete flaring tool for each tube size, and as a number of standard tube sizes exist a workman must purchase a variety of flaring tools to accommodate the various sizes, and the purchase of such a plurality of tools is expensive.
It is an object of the invention to provide a flaring tool of a universal type wherein the major components of the flaring tool may be used to accommodate a plurality of tube sizes to form special tube flares and heads, and wherein only a minor portion of the tool is changed to accommodate a particular tube size.
Another object of the invention is to provide a tube flaring tool of a universal type wherein the tool includes a threaded actuator upon which an interchangeable adapter is mounted, the adapter being the only component that needs to be specially sized to a given tube.
Yet a further object of the invention is to provide a manual tube flaring tool utilizing interchangeable adapters wherein the adapters may be readily interchanged upon a threaded actuator, and effectively maintain their connection upon the actuator during use.
In the practice of the invention a yoke includes an anvil surface upon which a tube holding bar can be selectively located. A threaded bore defined in the yoke receives a threaded actuator having an outer end which includes a handle for rotating the actuator, and the actuator inner end includes a tool head for forming the tube end. The head is in the form of an adapter having a threaded stem which is received within a threaded recess defined in the actuator inner end.
The threaded connection between the adapter and the actuator permits a variety of sizes of adapters to be selectively mounted upon the actuator thereby permitting the desired size of tube forming head to be attached to the actuator, and as the adapter is relatively small, the interchangeability thereof with respect to the actuator significantly reduces the cost of having a tool capable of accommodating a variety of tube sizes.
The lead of the threads attaching the adapter to the actuator screw differ from the lead of the actuator threads wherein the rotative torque that is imposed upon the adapter during flaring does not tend to loosen the adapter with respect to the actuator.